添加MgO对烧结产物还原性能的影响

通过热重法对烧结试样的还原率进行了测定,研究了MgO在不同温度和含量下对烧结试样还原性的影响,并结合显微矿相结构图进行了分析。研究表明:MgO对烧结产物还原性的影响,在850℃和1 220℃显示出不同的规律,低温下抑制铁氧化物的还原,高温下有利于还原性能的改善;另外,碱度对还原性能的作用也受MgO的影响,即碱度提高有助于改善烧结试样的高温还原性能,但这种促进和抑制作用随着MgO的加入而减弱。     

烃类蒸汽转化催化剂还原性能对活性的影响

烃类蒸汽转化制氢催化剂必须经过还原阶段,将其中的氧化镍还原为金属镍才具有催化转化活性。采用程序升温还原装置对实验室制备的催化剂的还原性能进行研究,并结合常压本征活性评价考察了还原气氛及还原温度对催化剂转化活性的影响。     

达钢高炉原料冶金性能研究

针对四川迭州钢铁集团有限责任公司的高炉失常,全面检测了高炉原料的冶金性能,提出烧结矿的低温还原粉化是导致高炉失常的主要原因。在采取措施改善烧结矿质量,使高炉恢复正常生产后．又对烧结矿的冶金性能进行了研究。     

复合镁质添加剂对球团生产影响的试验分析

球团矿作为一种优质的高炉炼铁原料,其配比不断增加.试验采用复合镁质添加剂代替膨润土,提高球团矿中的MgO含量,考察其对生球质量和球团冶金性能的影响规律和作用机理.试验结果表明,采用复合镁质添加剂代替膨润土后,生球抗压强度略有降低,落下次数变化不大,爆裂温度均高于600℃;球团矿的低温还原粉化指数(RDI+3.15)变化...     

一种新γ相氧化铝负载的铁铝双金属催化剂用于反向水煤气转化反应(英文)

In reverse water gas shift (RWGS) reaction CO₂ is converted to CO which in turn can be used to produce beneficial chemicals such as methanol. In the present study, Mo/Al₂O₃, Fe/Al₂O₃ and Fe-Mo/Al₂O₃ catalysts were synthesised using impregnation method. The structures of catalysts were studied using X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) method, inductively coupled plasma atomic emission spectrometer (ICP-AES), temperature programmed reduction (H₂-TPR), CO chemisorption, energy dispersive X-ray (EDX) and scanning electron microscopy (SEM) techniques. Kinetic properties of all catalysts were investigated in a batch reactor for RWGS reaction. The results indicated that Mo existence in structure of Fe-Mo/Al₂O₃ catalyst enhances its activity as compared to Fe/Al₂O₃. This enhancement is probably due to better Fe dispersion and smaller particle size of Fe species. Stability test of Fe-Mo/Al₂O₃ catalyst was carried out in a fixed bed reactor and a high CO yield for 60 h of time on stream was demonstrated. Fe₂(MoO₄)₃ phase was found in the structures of fresh and used catalysts. TPR results also indicate that Fe₂(MoO₄)₃ phase has low reducibility, therefore the Fe₂(MoO₄)₃ phase signifificantly inhibits the reduction of the remaining Fe oxides in the catalyst, resulted in high stability of Fe-Mo/Al₂O₃ catalyst. Overall, this study introduces Fe-Mo/Al₂O₃ as a novel catalyst with high CO yield, almost no by-products and fairly stable for RWGS reaction.     

CoCr_2O_4/SiO_2催化剂上二氯甲烷催化氧化

采用浸渍法制备了不同CoCr_2O_4负载量x CoCr_2O_4/SiO_2催化剂(x=5%、10%、20%和30%),考察其对二氯甲烷催化燃烧性能的影响。结果表明,催化剂的整体活性顺序为:30CoCr_2O_4/SiO_220CoCr_2O_4/SiO_210CoCr_2O_4/SiO_25CoCr_2O_4/SiO_2,但按照活性组分CoCr_2O_4质量归一化后本征活性顺序为:10CoCr_2O_4/SiO_2≈5CoCr_2O_4/SiO_220CoCr_2O_4/SiO_230CoCr_2O_4/SiO_2。表征结果发现催化剂本征活性与可还原性能和表面酸性存在密切关系。10CoCr_2O_4/SiO_2和5CoCr_2O_4/SiO_2具有较高的表面酸性和耗氢量,因此具有较高的本征活性。     

球团矿还原/膨胀试验机系统构成及控制原理

近些年来，我国一些钢铁企业和检验检疫机构陆续从国外引进球团矿还原／膨胀自动化检测设备，为我国铁矿石检测技术及效率的提高发挥了作用。为提高该类设备的应用效果和效率，以从日本中日本炉（工业）株式会社引进的球团矿还原／膨胀兼容试验机为例，介绍设备的工作程序和系统构成，分析设备的电气控制原理，并提出扩展设备功能的改造设想。     

A Novelγ-Alumina Supported Fe-Mo Bimetallic Catalyst for Reverse Water Gas Shift Reaction

In reverse water gas shift (RWGS) reaction CO2 is converted to CO which in turn can be used to pro-duce beneficial chemicals such as methanol. In the present study, Mo/Al2O3, Fe/Al2O3 and Fe-Mo/Al2O3 c...